Where does Libre get it’s various thresholds (SFP dBm, SFP voltage, fan speed, etc.) from? They don’t seem to correlate to what I see in the device’s CLI.
Hi,
Usually, if the values are published by the vendor we use those, if not we calculate the thresholds based on our measurements.
What devices are you looking at particularly?
The ones of the greatest interest are the SFP ports on our Cisco Nexus 9396.
LibreNMS:
Ethernet1/26 Lane 1 Transceiver 23.000m°C | 16.800m°C <> 38.400m°C
Ethernet1/26 Lane 1 Transceiver Voltage 3.000mV | 2.550mV <> 3.450mV
Ethernet1/26 Lane 1 Transceiver Bias Current 18.000mA | 0.000A <> 27.000mA
Ethernet1/26 Lane 1 Transceiver Transmit Power -3.000mdBm | -3.150mdBm <> -2.850mdBm
Ethernet1/26 Lane 1 Transceiver Receive Power -4.000mdBm | -4.200mdBm <> -3.800mdBm
Switch CLI:
IPLVINE-CISCO9396-01# show interface eth1/26 transceiver details
(snipped)
SFP Detail Diagnostics Information (internal calibration)
----------------------------------------------------------------------------
Current Alarms Warnings
Measurement High Low High Low
----------------------------------------------------------------------------
Temperature 23.22 C 90.00 C -5.00 C 85.00 C 0.00 C
Voltage 3.28 V 3.79 V 2.70 V 3.70 V 2.79 V
Current 18.34 mA 100.00 mA 0.00 mA 90.00 mA 0.10 mA
Tx Power -3.21 dBm 0.00 dBm -7.01 dBm -1.00 dBm -6.00 dBm
Rx Power -4.96 dBm 0.00 dBm -16.98 dBm -1.00 dBm -16.02 dBm
Transmit Fault Count = 0
----------------------------------------------------------------------------
I’m trying to figure out how to get that information via SNMP, but I’m not any good at that sort of thing.
CISCO-ENTITY-SENSOR-EXT-MIB talks about sensor thresholds, but I’m not good at figuring out what should be polled and if it actually has the information I’m looking for.
Secondarily, the fan speeds on my Brocade VDX-6720 have been alarming nearly forever and now that I look at the details, I can see why. It’s wanting a fan speed of exactly 100 RPM?
FAN #1 3.670kRPM | 100.000RPM <> 100.000RPM
FAN #2 3.450kRPM | 100.000RPM <> 100.000RPM
Post the output of ./discovery.php -h HOSTNAME -v -m sensors
So the brocade is because it uses ENTITY-MIB which doesn’t support high/low values so we calculate them ourselves. If you can find a mib that does provide this info we can add support.
For the cisco device. This is because entSensorThresholdSeverity is other for those sensors, at that stage we don’t use the provided info. We possibly could, happy to put a patch together if you want to test?
I’d be glad to test.
If I find something for the Brocade, I’ll follow up.
http://www.techhelp24.net/download/brocade/NOS/MIB/nos4.1.3c_all_mibs.tar.gz
That seems to be the MIBs for my OS version (or near it, anyway). The word sensor does exist in those files many times, though I don’t know if they actually apply.
Accurate thresholds for SFPs is particularly important because of differing requirements. For example, a 2km SFP may Tx between 0.5 dBm and -6.5 dBm and receive down to -8.4 dBm. A 160 km SFP may Tx between 0 and 5 dBm and Rx down to -35 dBm.
I also just noticed that none of the SFP values pulled by Libre seem to be correct. I’m not sure thresholds matter much if the value isn’t correct to start with.
SFP Detail Diagnostics Information (internal calibration)
----------------------------------------------------------------------------
Current Alarms Warnings
Measurement High Low High Low
----------------------------------------------------------------------------
Temperature 33.25 C 90.00 C -45.00 C 85.00 C -40.00 C
Voltage 3.31 V 3.63 V 2.97 V 3.46 V 3.13 V
Current 25.93 mA 100.00 mA 2.00 mA 80.00 mA 4.00 mA
Tx Power -4.90 dBm -2.21 dBm -10.00 dBm -3.00 dBm -9.03 dBm
Rx Power -5.65 dBm 3.01 dBm 0.00 dBm 0.00 dBm -30.00 dBm
Transmit Fault Count = 0
----------------------------------------------------------------------------
Note: ++ high-alarm; + high-warning; -- low-alarm; - low-warning
All values actually seem to be off by a factor of 1000.
Anything else we can do here?